Water, although soft and compliant at low speed, is hard and non-compressible at high speed. Therefore, a wave at 10 knots is displaced whereas at 100 knots is very difficult to displace. Travel over a surface at high speed requires an entirely different mechanism than traveling over that same surface at slow speed. The slow speed being that which we feel when a normal unassisted human contacts the water.
While traveling in a high velocity vehicle, the characteristics of a sea state can therefore appear to change so that resembling a hilly desert or rocky terrain which will rapidly destroy an un-cushioned or non-suspended vehicle attempting to travel across this surface at high speed.
The typical approach to high speed water travel has been hydroplanes or surface effect vehicles which rise slightly above the wave action either by:
(a) riding on a column of air trapped between two sponsons which contact the water surface. This action is known as flying "in ground effect" and, although possible, is inherently unstable, as executed by the typical hydroplane with no controllable air foils. This situation is like flying an airplane without horizontal and vertical stabilizers, trim, flaps etc., i.e., flight without control, precariously balanced on a column of air, subject to blow over with the slightest change of wind or wave condition.
(b) riding on a bubble of air created by forcing air into an area beneath the hull, which is encircled by a skirt or flexible seal, thereby creating an area of higher pressure beneath the hull which lifts the craft off the surface of the water. This system requires large docking or landing areas, similar to airports, in which to operate due to a lack of accurate steerage and immediate control.